1. Technical Field
The present invention relates to a technology in which liquid in a liquid container which receives the liquid is detected.
2. Related Art
Similarly to a so-called ink jet printer, a liquid container such as an ink cartridge, inside of which ink is contained as an ink supply source, is mounted in a liquid ejecting apparatus which ejects liquid such as ink from an ejection nozzle. The liquid container is mounted so as to be replaced with respect to the liquid ejecting apparatus, and is able to be replaced to a new liquid container when the liquid in the liquid container is run out.
In addition, in order to inform a user when to replace the liquid container, a liquid container is provided which includes a liquid detection device for detecting that liquid in the container has run out, between a liquid reception unit which receives liquid and a supply port which supplies the received liquid to the outside of the liquid container. The liquid detection device is provided with a cavity which is formed of a concave portion and a film which covers the concave portion, and the inside thereof is filled with the liquid from the liquid reception unit. In addition, a pressure reception plate and a spring are provided in the inside of the cavity, and the spring urges the film to one side through the pressure reception plate. In such a liquid detection device, when the liquid remains in the liquid reception unit, the pressure of the liquid and the pressure from the spring are applied to the film which covers the concave portion, since the liquid is supplied to the cavity. However, when the liquid in the liquid reception unit runs out, the pressure of the liquid is not applied to the film, and the position of the film (and the pressure reception plate) moves, since the liquid is not supplied to the cavity. A technology is proposed in JP-A-2007-307894, in which the fact that the liquid in the liquid reception unit has run out is detected, by detecting the change in the position of the pressure reception plate at this time.
However, in the above described related art, there was a problem in that bubbles accumulated at the rear side portion of the pressure reception plate where the pressure reception plate came into close contact with the spring. As a result, there was a problem in that it was not easy to appropriately detect that the liquid in the liquid reception unit had run out, since bubbles remained in the cavity.